Expediting H2 Evolution over MAPbI3 with a Nonnoble Metal Cocatalyst Mo2C under Visible Light

Abstract

Halide perovskites have been emerging as promising photocatalytic materials for H2 evolution from water due to their outstanding photoelectric properties. However, the lack of proper surface reactive sites greatly hinders the photocatalytic potential of these fascinating compounds. Here, Mo2C nanoparticles have been anchored onto methylammonium lead iodide (MAPbI3) as a nonnoble metal cocatalyst to promote H2 evolution reactions. The Mo2C nanoparticles have opposite zeta potential with MAPbI3 thereby electrostatically assembled onto the MAPbI3 surface, i.e., Mo2C@MAPbI3. Our results show that the anchored Mo2C nanoparticles have a strong interplay with MAPbI3 substrate so that photogenerated electrons of MAPbI3 can be rapidly separated and transferred into Mo2C for further H2 evolution reactions. Under optimal conditions, Mo2C@MAPbI3 delivers exceptionally high photocatalytic performance for visible light-driven H2 evolution that clearly outperforms pristine MAPbI3 and Pt-deposited MAPbI3. An apparent quantum efficiency as high as 12.65% at 600±40 nm has been attained for H2 evolution, surpassing most of the MAPbI3-based photocatalyst reported. These results signify the usefulness and applicability of Mo2C as a new nonnoble metal-based cocatalyst in solar water splitting.